Surfboard fin



FIG. 1 is a front, top and right side perspective view of a surfboard fin, showing my new design;

FIG. 2 is a rear, bottom and left side perspective view thereof;

FIG. 3 is a front elevation view thereof;

FIG. 4 is a rear elevation view thereof;

FIG. 5 is a left side elevation view thereof;

FIG. 6 is a right side elevation view thereof;

FIG. 7 is a top plan view thereof;

FIG. 8 is a bottom plan view thereof; and,

FIG. 9 is another front, top and right side perspective view thereof, shown in a condition of use.

The broken lines shown in FIG. 9 illustrate the environment of the claimed design and form no part thereof. 

CLAIM The ornamental design for a surfboard fin, as shown and described. 